1 #include <linux/kernel.h>
2 #include <linux/init.h>
3 #include <linux/module.h>
4 #include <linux/proc_fs.h>
5 #include <linux/skbuff.h>
6 #include <linux/netfilter.h>
7 #include <linux/seq_file.h>
8 #include <net/protocol.h>
9 #include <net/netfilter/nf_log.h>
11 #include "nf_internals.h"
13 /* Internal logging interface, which relies on the real
16 #define NFLOGGER_NAME_LEN 64
18 static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly;
19 static DEFINE_MUTEX(nf_log_mutex);
21 #define nft_log_dereference(logger) \
22 rcu_dereference_protected(logger, lockdep_is_held(&nf_log_mutex))
24 static struct nf_logger *__find_logger(int pf, const char *str_logger)
26 struct nf_logger *log;
29 for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
30 if (loggers[pf][i] == NULL)
33 log = nft_log_dereference(loggers[pf][i]);
34 if (!strncasecmp(str_logger, log->name, strlen(log->name)))
41 int nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
43 const struct nf_logger *log;
45 if (pf == NFPROTO_UNSPEC || pf >= ARRAY_SIZE(net->nf.nf_loggers))
48 mutex_lock(&nf_log_mutex);
49 log = nft_log_dereference(net->nf.nf_loggers[pf]);
51 rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
53 mutex_unlock(&nf_log_mutex);
57 EXPORT_SYMBOL(nf_log_set);
59 void nf_log_unset(struct net *net, const struct nf_logger *logger)
62 const struct nf_logger *log;
64 mutex_lock(&nf_log_mutex);
65 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
66 log = nft_log_dereference(net->nf.nf_loggers[i]);
68 RCU_INIT_POINTER(net->nf.nf_loggers[i], NULL);
70 mutex_unlock(&nf_log_mutex);
73 EXPORT_SYMBOL(nf_log_unset);
75 /* return EEXIST if the same logger is registered, 0 on success. */
76 int nf_log_register(u_int8_t pf, struct nf_logger *logger)
81 if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers))
84 mutex_lock(&nf_log_mutex);
86 if (pf == NFPROTO_UNSPEC) {
87 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
88 if (rcu_access_pointer(loggers[i][logger->type])) {
93 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
94 rcu_assign_pointer(loggers[i][logger->type], logger);
96 if (rcu_access_pointer(loggers[pf][logger->type])) {
100 rcu_assign_pointer(loggers[pf][logger->type], logger);
104 mutex_unlock(&nf_log_mutex);
107 EXPORT_SYMBOL(nf_log_register);
109 void nf_log_unregister(struct nf_logger *logger)
111 const struct nf_logger *log;
114 mutex_lock(&nf_log_mutex);
115 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
116 log = nft_log_dereference(loggers[i][logger->type]);
118 RCU_INIT_POINTER(loggers[i][logger->type], NULL);
120 mutex_unlock(&nf_log_mutex);
123 EXPORT_SYMBOL(nf_log_unregister);
125 int nf_log_bind_pf(struct net *net, u_int8_t pf,
126 const struct nf_logger *logger)
128 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
130 mutex_lock(&nf_log_mutex);
131 if (__find_logger(pf, logger->name) == NULL) {
132 mutex_unlock(&nf_log_mutex);
135 rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
136 mutex_unlock(&nf_log_mutex);
139 EXPORT_SYMBOL(nf_log_bind_pf);
141 void nf_log_unbind_pf(struct net *net, u_int8_t pf)
143 if (pf >= ARRAY_SIZE(net->nf.nf_loggers))
145 mutex_lock(&nf_log_mutex);
146 RCU_INIT_POINTER(net->nf.nf_loggers[pf], NULL);
147 mutex_unlock(&nf_log_mutex);
149 EXPORT_SYMBOL(nf_log_unbind_pf);
151 void nf_logger_request_module(int pf, enum nf_log_type type)
153 if (loggers[pf][type] == NULL)
154 request_module("nf-logger-%u-%u", pf, type);
156 EXPORT_SYMBOL_GPL(nf_logger_request_module);
158 int nf_logger_find_get(int pf, enum nf_log_type type)
160 struct nf_logger *logger;
163 if (pf == NFPROTO_INET) {
164 ret = nf_logger_find_get(NFPROTO_IPV4, type);
168 ret = nf_logger_find_get(NFPROTO_IPV6, type);
170 nf_logger_put(NFPROTO_IPV4, type);
177 if (rcu_access_pointer(loggers[pf][type]) == NULL)
178 request_module("nf-logger-%u-%u", pf, type);
181 logger = rcu_dereference(loggers[pf][type]);
185 if (try_module_get(logger->me))
191 EXPORT_SYMBOL_GPL(nf_logger_find_get);
193 void nf_logger_put(int pf, enum nf_log_type type)
195 struct nf_logger *logger;
197 if (pf == NFPROTO_INET) {
198 nf_logger_put(NFPROTO_IPV4, type);
199 nf_logger_put(NFPROTO_IPV6, type);
203 BUG_ON(loggers[pf][type] == NULL);
206 logger = rcu_dereference(loggers[pf][type]);
207 module_put(logger->me);
210 EXPORT_SYMBOL_GPL(nf_logger_put);
212 void nf_log_packet(struct net *net,
214 unsigned int hooknum,
215 const struct sk_buff *skb,
216 const struct net_device *in,
217 const struct net_device *out,
218 const struct nf_loginfo *loginfo,
219 const char *fmt, ...)
222 char prefix[NF_LOG_PREFIXLEN];
223 const struct nf_logger *logger;
227 logger = rcu_dereference(loggers[pf][loginfo->type]);
229 logger = rcu_dereference(net->nf.nf_loggers[pf]);
233 vsnprintf(prefix, sizeof(prefix), fmt, args);
235 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
239 EXPORT_SYMBOL(nf_log_packet);
241 void nf_log_trace(struct net *net,
243 unsigned int hooknum,
244 const struct sk_buff *skb,
245 const struct net_device *in,
246 const struct net_device *out,
247 const struct nf_loginfo *loginfo, const char *fmt, ...)
250 char prefix[NF_LOG_PREFIXLEN];
251 const struct nf_logger *logger;
254 logger = rcu_dereference(net->nf.nf_loggers[pf]);
257 vsnprintf(prefix, sizeof(prefix), fmt, args);
259 logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
263 EXPORT_SYMBOL(nf_log_trace);
265 #define S_SIZE (1024 - (sizeof(unsigned int) + 1))
269 char buf[S_SIZE + 1];
271 static struct nf_log_buf emergency, *emergency_ptr = &emergency;
273 __printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...)
278 if (likely(m->count < S_SIZE)) {
280 len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
282 if (likely(m->count + len < S_SIZE)) {
288 printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
291 EXPORT_SYMBOL_GPL(nf_log_buf_add);
293 struct nf_log_buf *nf_log_buf_open(void)
295 struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC);
300 m = xchg(&emergency_ptr, NULL);
306 EXPORT_SYMBOL_GPL(nf_log_buf_open);
308 void nf_log_buf_close(struct nf_log_buf *m)
310 m->buf[m->count] = 0;
311 printk("%s\n", m->buf);
313 if (likely(m != &emergency))
320 EXPORT_SYMBOL_GPL(nf_log_buf_close);
322 #ifdef CONFIG_PROC_FS
323 static void *seq_start(struct seq_file *seq, loff_t *pos)
325 struct net *net = seq_file_net(seq);
327 mutex_lock(&nf_log_mutex);
329 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
335 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
337 struct net *net = seq_file_net(s);
341 if (*pos >= ARRAY_SIZE(net->nf.nf_loggers))
347 static void seq_stop(struct seq_file *s, void *v)
349 mutex_unlock(&nf_log_mutex);
352 static int seq_show(struct seq_file *s, void *v)
355 const struct nf_logger *logger;
357 struct net *net = seq_file_net(s);
359 logger = nft_log_dereference(net->nf.nf_loggers[*pos]);
362 seq_printf(s, "%2lld NONE (", *pos);
364 seq_printf(s, "%2lld %s (", *pos, logger->name);
366 if (seq_has_overflowed(s))
369 for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
370 if (loggers[*pos][i] == NULL)
373 logger = nft_log_dereference(loggers[*pos][i]);
374 seq_printf(s, "%s", logger->name);
375 if (i == 0 && loggers[*pos][i + 1] != NULL)
378 if (seq_has_overflowed(s))
382 seq_printf(s, ")\n");
384 if (seq_has_overflowed(s))
389 static const struct seq_operations nflog_seq_ops = {
396 static int nflog_open(struct inode *inode, struct file *file)
398 return seq_open_net(inode, file, &nflog_seq_ops,
399 sizeof(struct seq_net_private));
402 static const struct file_operations nflog_file_ops = {
403 .owner = THIS_MODULE,
407 .release = seq_release_net,
414 static char nf_log_sysctl_fnames[NFPROTO_NUMPROTO-NFPROTO_UNSPEC][3];
415 static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
417 static int nf_log_proc_dostring(struct ctl_table *table, int write,
418 void __user *buffer, size_t *lenp, loff_t *ppos)
420 const struct nf_logger *logger;
421 char buf[NFLOGGER_NAME_LEN];
423 int tindex = (unsigned long)table->extra1;
424 struct net *net = table->extra2;
427 struct ctl_table tmp = *table;
429 /* proc_dostring() can append to existing strings, so we need to
430 * initialize it as an empty string.
434 r = proc_dostring(&tmp, write, buffer, lenp, ppos);
438 if (!strcmp(buf, "NONE")) {
439 nf_log_unbind_pf(net, tindex);
442 mutex_lock(&nf_log_mutex);
443 logger = __find_logger(tindex, buf);
444 if (logger == NULL) {
445 mutex_unlock(&nf_log_mutex);
448 rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
449 mutex_unlock(&nf_log_mutex);
451 struct ctl_table tmp = *table;
454 mutex_lock(&nf_log_mutex);
455 logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
457 strlcpy(buf, "NONE", sizeof(buf));
459 strlcpy(buf, logger->name, sizeof(buf));
460 mutex_unlock(&nf_log_mutex);
461 r = proc_dostring(&tmp, write, buffer, lenp, ppos);
467 static int netfilter_log_sysctl_init(struct net *net)
470 struct ctl_table *table;
472 table = nf_log_sysctl_table;
473 if (!net_eq(net, &init_net)) {
474 table = kmemdup(nf_log_sysctl_table,
475 sizeof(nf_log_sysctl_table),
480 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
481 snprintf(nf_log_sysctl_fnames[i],
483 nf_log_sysctl_table[i].procname =
484 nf_log_sysctl_fnames[i];
485 nf_log_sysctl_table[i].maxlen = NFLOGGER_NAME_LEN;
486 nf_log_sysctl_table[i].mode = 0644;
487 nf_log_sysctl_table[i].proc_handler =
488 nf_log_proc_dostring;
489 nf_log_sysctl_table[i].extra1 =
490 (void *)(unsigned long) i;
494 for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
495 table[i].extra2 = net;
497 net->nf.nf_log_dir_header = register_net_sysctl(net,
498 "net/netfilter/nf_log",
500 if (!net->nf.nf_log_dir_header)
506 if (!net_eq(net, &init_net))
512 static void netfilter_log_sysctl_exit(struct net *net)
514 struct ctl_table *table;
516 table = net->nf.nf_log_dir_header->ctl_table_arg;
517 unregister_net_sysctl_table(net->nf.nf_log_dir_header);
518 if (!net_eq(net, &init_net))
522 static int netfilter_log_sysctl_init(struct net *net)
527 static void netfilter_log_sysctl_exit(struct net *net)
530 #endif /* CONFIG_SYSCTL */
532 static int __net_init nf_log_net_init(struct net *net)
536 #ifdef CONFIG_PROC_FS
537 if (!proc_create("nf_log", S_IRUGO,
538 net->nf.proc_netfilter, &nflog_file_ops))
541 ret = netfilter_log_sysctl_init(net);
548 #ifdef CONFIG_PROC_FS
549 remove_proc_entry("nf_log", net->nf.proc_netfilter);
554 static void __net_exit nf_log_net_exit(struct net *net)
556 netfilter_log_sysctl_exit(net);
557 #ifdef CONFIG_PROC_FS
558 remove_proc_entry("nf_log", net->nf.proc_netfilter);
562 static struct pernet_operations nf_log_net_ops = {
563 .init = nf_log_net_init,
564 .exit = nf_log_net_exit,
567 int __init netfilter_log_init(void)
569 return register_pernet_subsys(&nf_log_net_ops);